Infrared device



May 29, 1956 s KQZBELT 2,748,247

INFRARED DEVICE Filed April 10, 1953 2 Sheets-Sheet 1 Fig.1

INVENT /2 gym 5. KOZB INFRARED DEVICE Lloyd S. Kozbelt, Pittsburgh, Pa.,assignor to Edwin L. Wiegand Company, Pittsburgh, Pa., a corporation ofPennsylvania Application April 10, 1953, Serial No. 347,929

1 Claim. (Cl. 219-34) My invention relates to an infrared device, moreparticularly to an infrared device having a sheathed-type electricresistance element, and the principal object of my invention is toprovide new and improved devices of the character described.

The wide usage of electric infrared devices in modern day industries iswell known. These devices find application wherever it is desirable toemploy a concentrated, clean, easily regulated source of heat forpurposes such as drying and the like. In the past, glass infrared lampshave been employed; however, these lamps have not been entirelysatisfactory.

Some of the disadvantages of the commonly used infrared lamps are asfollows: Since infrared lamps are constructed of glass, they are easilybroken if they are struck by an object or if they are splashed withwater or other liquid when hot. Infrared lamps also have a relativelyshort life which will be further materially reduced if the lamps aresubjected to shock or vibration.

In contrast, an infrared device constructed in accordance with myinvention possesses none of the disadvantages possessed by prior artdevices. Other advantages of my invention will be understood from astudy of the following description and of the drawings appended here to.

In the drawings accompanying this specification and forming a part ofthis application there is shown, for purpose of illustration, anembodiment which my invention may assume, and in these drawings:

Figure 1 is a fragmentary plan view of an infrared device embodying myinvention,

Figure 2 is an elevational view of the embodiment shown in Figure 1,certain parts being broken away to better illustrate interiorconstruction,

Figure 3 is an enlarged fragmentary sectional view generallycorresponding to the line 33 of Figure l, and

Figure 4 is a further enlarged fragmentary sectional view generallycorresponding to the line 44 of Figure 3.

As illustrated, my improved infrared device comprises a sheathedelectric resistance element in combination with a reflector 11 and aterminal mounting block 12. The element It is constructed in accordancewith Wellknown principles and comprises a tubular sheath 13 filled withcompacted refractory material in which is imbedded the usual coiledresistance wire. In the present embodiment, the coiled resistance wireterminates short of respective ends of the sheath and each end of theresistance wire is secured to a respective terminal pin 14 that extendsfrom a respective end of the sheath 13 to provide for a terminalconnection later to be described.

As will be understood, the portion of the sheathed element 10intermediate the ends and containing the coiled resistance wire iscommonly known as the active or heat generating portion. In thepresently disclosed embodiment, this active portion is formed to providea generally rectilinear portion having a pair of arcuate portionsdisposed in the plane of the rectilinear portion, each arcuate portionextending from a respective end of the rectilinear 2348,24? Patented May29, 1956 portion and curving back toward the opposite end of therectilinear portion. As shown, this construction provides a compactray-generating area having a configuration substantially that of thefigure 8 and which is substantially flat and which will radiate infraredrays in a uniform pattern that is devoid of dead spots.

As illustrated, leg portions 15 extend from the active portion of theelement 10 and the leg portions are adapted to be secured together bymeans of a clip 16. In the presently disclosed embodiment, the clip 16is formed of sheet metal or the like to provide a generally planeportion 17 having spaced-apart apertures each adapted to receive arespective leg 15. As best seen in Figure 4, each leg portion extendsthrough a respective aperture in the clip 16 and is secured thereto, asby brazing or any other suitable means.

With reference to the position of parts shown in Figure 4, oppositeportions 18 of the clip 16 are each bent to a position underlying theportion 17 and generally parallel therewith, each portion 18 beingfurther bent downwardly to provide portions 19 which lie in respectiveplanes that are angled toward the axes of the leg portions 15 as shown.As will be clear, the clip 16 serves to secure the leg portions 15together and also serves other purposes which will later be shown.

As illustrated in Figure 4 and as previously mentioned, each terminalpin 14 extends beyond the end of its respective leg portion 15. Acoupling sleeve 26 is disposed about each pin 14 and each sleeve issecured to its respective pin 14 in spaced relation to a respective leg15 by any suitable means such as, for example, by crimping the sleeve at21. Dielectric means such as a plurality of mica washers 22 areinterposed between each sleeve and its respective leg 15 in order tospace the sleeve from the leg.

Each sleeve 2%? extends beyond the end of its terminal pin 14 to form apocket for receiving an elongated flexible electrical conductor orpig-tail lead 23. Each lead 23 is adapted to be disposed in itsrespective pocket and each may be secured in place by silver solder orother suitable means.

As previously mentioned, and as shown in Figures 1 and 2, the element 10is adapted to be used in combination with a reflector 111 and a terminalmounting block 12. The presently disclosed embodiment illustrates thereflector 11; as formed integrally with a sheet-metal, boxlike reflectorhousing 24. It will be apparent that a plurality of reflectors could beformed in a single housing or that any other suitable construction couldbe employed.

The housing 24- is apertured at 25 (see Figure 2) to receive the block12, the block being secured to the under surface of the housing asshown, by means of screws 26 which pass through apertures in the housingand are threaded into the block.

The block 112 is provided with a boss portion 27 intermediate its ends(see Figures 2 and 3) and such portion extends through the aperture 25in the housing 24. As best seen in Figures 3 and 4, the portion 27 isrecessed to provide opposed inclined walls 28, and the block is providedwith spaced-apart apertures 29 for a purpose to be disclosed. Oppositeends of the block 12 are recessed at 30 to receive terminal clips 31that are secured to the block by means of screws 32. Channels 33 areformed in the lower surface of the block 12 and each channel extendsfrom one of the apertures 29 to an adjoining recess 3d.

The element 10 is adapted to be supported by the block 12 in fixedrelation with the reflector 11 in the following manner: The legs 15 ofthe element 10 will first be inserted through an aperture 34 in thereflector Ill so that the sleeves 2t) and the leads 23 are disposedWithin respective apertures 29 and whereby the portions 18 and 19 of theclip 16 respectively abut the upper surface of the block portion 27 andthe inclined walls 23 of the recess formed in the portion 27. As will beclear, the active or heat generating portion 13 of the element 1% willthus be correctly positioned with respect to the reflector 11, andparticularly, the active portion will be maintained in predeterminedspaced relation with the plane of the outer surface of the reflector.

As clearly shown in Figure 3, the element is adapted to be secured inposition to the block 12 by fastening the free end of each of the leads23 to a respective terminal clip by any suitable means, each lead 23lying in a respective channel 33 of mounting block 12 as shown. Theelectric powerline may then be connected to the terminal clips 31 inorder to eiiect operation of my improved infrared device.

in view of the foregoing it will be apparent to those skilled in the artthat I have accomplished at least the principal object of my inventionand it will also be apparent to those skilled in the art that theembodiment herein described may be variously changed and modified,Without departing from the spirit of the invention, and that theinvention is capable of uses and has advantages not herein specificallydescribed, hence it will be appreciated that the herein disclosedembodiment is illustrative only, and that my invention is not limitedthereto.

I claim:

An infra-red device for use in heating by radiation, comprising abowl-like reflector having a central aperture, an elongatedmetallic-sheathed electrical resistance element disposed in fixedposition within the reflector bowl, said element having an intermediateheat generating portion of configuration like the figure 8 including arectilinear central portion and two oppositely disposed arcuate portionsdisposed in a common plane and respectively continuing from oppositeends of said rectilinear portion and curving back to the ends of thelatter opposite to the ends from which the respective opposite arcuateportions originate, said rectilinear portion being disposed between andconnecting said arcuate portions in the plane thereof, said resistanceelement further including a pair of coplanar straight non-heatgenerating sections respectively continuing from said arcuate portionsand disposed in spaced parallel relation to and on opposite sides ofsaid rectilinear portion, the free ends of said straight sections beingbent into a plane normal to the plane of said heating portion of theelement and disposed in spaced proximity to constitute terminal portionsextending through said reilector aperture for connection to a source ofelectrical energy, whereby said intermediate radiant heating portion ofsaid resistance element is co-extensive only with said rectilinearcentral portion and the opposed connected arcuate portions, saidstraight sections and said terminal portions of the element beingrelatively free of heat to minimize mutual heating between adjacentparts of said resistance element.

References Eited in the file of this patent UNiTED STATES PATENTS1,393,368 Henry Oct. 11, 1921 1,531,414 Ruben Mar. 31, 1925 1,580,090Schoenberg Apr. 6, 1926 2,068,423 Manser Jan. 19, 1937 2,161,793Beaucolin June 13, 1939 2,303,873 Anderson Dec. 1, 1942 2,325,358Andrews July 27, 1943 2,455,186 McCormick Nov. 30, 1948 2,514,618 AncellJuly 11, 1950 2,615,117 Tillapaugh Oct. 21, 1952 2,712,587 Story July 5,1955 FOREIGN PATENTS 680,553 Germany Aug. 31, 1939

